Lighted push button switch with latching mechanism



J. R. BAILEY Jan. 12, 1965 LIGHTED PUSH BUTTON SWITCH WITH LATCI-IING MECHANISM Filed April 2. 1962 I an I5 33 12, mw

1NVENTOR.'- JAMES R. BAILEY BY:..

ATT'YS United States Patent 3,165,612 LIGHTED PUSH BUTTGN SWITCH WlTH LATCIHNG MECHANISM James K. Bailey, Chicago, Ill., assignor to Switchcrai't, Inc., Chicago, 111., a corporation of Illinois Fiied Apr. 2, 1962, Ser. No. 134,235 15 Claims. (Cl. 200-459) The present invention relates in general to latch mechanism, and has more particular reference to latching means adapted to be latched and released in response to successive operation of an actuating member, the invention pertaining specifically to electrical switch apparatus alternately disposable in relatively shifted switching positions in response to successive projections, from a normal retracted rest position, of an actuating member, such as a pushbutton.

An important object of the present invention is to provide improved latching and latch releasing means operable to latch a reciprocably movable member in one of its relatively shifted positions, in response to movement of the member to a projected latch actuating position, and to release the latch to permit the member to return to its other relatively shifted position, in response to a successive projection of the member to latch actuating position; a further object being to provide a latch comprising a pair of relatively flat plates mounted in stacked relation one upon the other and relatively reciprocable for the actuation of latching means formed and mounted thereon, whereby the depth of said cooperating plate members is a minimal dimension not greater than the combined thicknesses of the plates; a still further object being to mount a shiftable latching element on one of the cooperating plates in position extending Within an opening formed in the other plate and providing latch actuating shoulders and fingers in position to shift the latching element successively into latching and releasing positions as the plates are successively projected the one upon the other, to latch actuating position, whereby the latching element and its operating means are disposed entirely within the space defined by the combined thickness of the cooperating plates.

Another important object is to form one of the cooperating plates with a mounting bracket for the attachment of the latching mechanism in a carrying structure in which it is to be mounted for use, thereby constituting the bracket mounted plate as a support frame for the latching mechanism, the other of said cooperating plates having an attached pushbutton or other means for shifting it upon the support frame; a further object being to incorporate the improved latching mechanism in an electrical switch structure by mounting switching elements upon the plates in position to be actuated in response to relative plate movement.

Another important object is to provide a biasing spring connected between the relatively shiftable plates in position to normally urge one of the plates in one direction on the other toward a normal, retracted or standby position determined by cooperating stops formed on the plates, means being connected on one of the plates for shifting it upon the other against the influence of the spring to a projected position conveniently defined by cooperating stops formed on the plates, means being provided on one plate for shifting the latching element, on the other plate, in response to projecting movement of the plates, into position to retain the plates in latched condition upon retrogression of the plates from fully projected position to a slightly retracted latching position, under the influence of the biasing spring, the latch actuating means, in response to movement of the plates, from such slightly retracted latched position to fully projected position, being operable to turn the latch element from plate latching 'ice position and thus release the same to permit the biasing spring to return the plates to fully retracted position.

Another important object is to provide improved electrical switch mechanism by forming one of the relatively movable plates as a mounting for spring biased switches and to provide the other plate with switch actuating cams disposed in position thereon permitting the switches each to assume a spring biased switching position, when the relatively shiftable switch latching and releasing plates are in relatively retracted position, and to shift the biased switches, against the influence of the biasing springs, to a shifted switch position, and to hold the same in such shifted position, when said plates are in relatively projected and latched position; a further object being to provide for mounting the spring biased switches upon the support plate while attaching the switch actuating cam means upon the cooperating relaswitch for energizing the lamp only when the latchable structure is in one of its relatively shifted positions; a still further object being to provide a switch for causing the lamp to be energized only when the relatively movable plates are in relatively projected position,

Briefly stated, a preferred embodiment of the invention may comprise an elongated support plate carrying a turnable latch thereon, intermediate its ends, and formed at one end with a mounting bracket, and a flat latch actuating plate overlying the support plate and reciprocable longitudinally thereof between retracted and projected positions determined by cooperating stop means formed on said plates, the latch actuating plate extending through and being guided in an opening formed in the mounting bracket, said latch actuating plate preferably having a pushbutton element secured thereto and extending on the side of the bracket remoteofrom said support plate.

In order to normally urge the latch actuating plate toward a retracted position on the support plate determined by cooperating stops formed on the plates, a biasing spring is preferably connected between the plates.

In order to turn the latch between latching and releasing positions on the support plate, the latch actuating plate may be formed with an opening providing a pair of mutually normal internal abutments forming a latching.

corner and a latch turning finger. The latch may comprise a generally rectangular strip of material having notches formed in its opposite ends, the strip being normally oriented on the support plate in position to receive the latch actuating finger, as the latch actuating plate is projected from retracted to fully projected position on the support plate, as by moving the pushbutton against the influence of the biasing spring. Application of the notched end of the latch against the finger will serve to turn the latch through an angle of the order of forty-five degrees to presentits opposite notched end in position to engage the latching corner on the actuating plate, when the pushbuttton is released. Accordingly, the plate will be latched in position slightly retracted from its fully projected position, as the result of retrograde movement of the latch actuating plate upon release of the pushbutton.

The latch actuating finger may also be disposed in position to turn the latch element, in response to push- Patented Jan. 12, 1965 button operation when the device is latched, in order to dispose the latch in position normal to its initial or standby position, so that the latch, upon release of the pushbutton, may be returned to its standby position, by the action of the abutment upon the transversely disposed latching element.

The support plate, at its bracket remote end, may be formed as a mounting for one or more leaf spring switches embodying shiftable switch 'actuating'blades normally biased into one switching position. The shiftable switch actuating plate may have cams mounted thereon in position permitting the switch blades to occupy such biased position when the latch actuating plate is inretracted position under the influence of its biasing spring, said cams being formed to shift the switch blades to a shifted switching position when the latch actuating plate is projected away from its normal retracted position, as when the same is held in latched position.

The pushbutton element preferably forms a housing for a signal lamp and provides a translucent portion adapted to be illuminated by the lamp when energized. Lamp energizing conductors may be provided in the pushbutton element, with the ends of the conductors exposed outwardly of the plate connected end of the pushbutton element. The exposed ends of the conductors may have wiping engagement with a pair of preferably blade-like supply conductors mounted on the support plate in position to ride upon and contact with the exposed ends of the lamp energizing conductors, during movementof the latch actuating plate on the support plate. A blade lifting cam may be formed on one of the blade-like supply conductors in position to cooperatewith a cam actuating button on the latch actuating plate, to break the connection of the supply conductor with the exposed end of the lamp energizing conductor which it wipes when the latch actuating plate and its attached pushbutton element are in retracted position. As a consequence, the lamp will be energized only when the pushbutton element and the latch actuating plate are in projected position.

The foregoing and numerous other important objects, advantages and inherent functions of the invention will become apparent as the same is more fully understood from the following description, which, taken in connection with the accompanying drawings, discloses a preferred embodiment of the invention.

Referring to the drawings:

FIG. 1 is a side view of a pushbutton switch embodying the present invention;

FIG. 2 comprises a showing, in perspective, of C0111- ponent parts of the structure illustrated in FIG. 1;

FIG. 3 is a sectional view taken substantially along the line 33 in FIG. 1;

FIGS. 4, 5, 6 and 7 respectively show the relative position of the latch actuating parts of the structure in normal retracted or standby position, in fully projected position prior to latching of the parts, in latching position slightly retracted from projected position, and in projected latch releasing position immediately prior to return of the components to standby or retracted position; and

FIGS.- 4a, 5a and 6a respectively show the relative position of the switch forming components of the structure respectively when the latch actuating plate and its connected pushbutton are in normal retracted or standby position, when they are in either of the fully projected positions shown in FIGS. 5 and 7, and when they are in the latched position shown in FIG. 6.

To illustrate the invention the drawings show an electrical switching mechanism 11 adapted for adjustment selectively in a plurality of relatively shifted positions and reciprocable switch actuating means 13 operable to shift the mechanism between said relatively shifted positions in response to successive projections of the switch actuating means from normal retracted position. As shown, the switch actuating means compiises a pushbutton structure biased toward normal retracted position by a spring 15 and manually operable, as by finger pressure, to shift the mechanism toward projected position against the contrary influence of the spring.

It will be understood, of course, that the invention in its broader aspects is not necessarily limited to a manually operable pushbutton structure, but that the reciprocable actuating means may be operated by any convenient mechanical or electrical thrusting device, if desired; and it will be likewise appreciated that the invention need not necessarily be limited to an adjustable or driven device comprising electrical switching mechanism, but may, if desired, comprise any device adapted. to be adjusted or set in a plurality of relatively shifted positions.

Mechanism embodying the present invention, however, is particularly useful when embodied in pushbutton actuated electrical switches. As a consequence, the drawings show electrical switches in association with actuating means embodying latch mechanism comprising a pair of flat relatively reciprocable plates 1'7 and 19 stacked one upon another, and normally urged by the spring 15 toward a normal relatively retracted or standby position determined by cooperating stops formed on said plates. Means is provided for relatively moving the plates against the influence of the spring 15 to a projected position determined by cooperating stops formed on said plates. The cooperating stops may comprise the opposite ends 24) and 22 of a longitudinally extending slot 21 formed in one of the plates, and a headed pin 23 mounted in the other, in position extending in the slot and serving to hold the plates together for relative longitudinal movement.

A latching element 24 is mounted for shifting movement medially on one of the plates in position extending within a cavity or opening 26 formed in the other plate. The latching element 24 preferably comprises a rectangular piece of metal medially pivoted on a pin 25 secured medially on the plate 17, the opposed ends of the element being formed with notches 24'. The opening 26 has a relatively wide portion 2'7 at one end and a narrower portion 28 thereof at the other, said portions having alined edges forming one side 29 of the opening and relatively offset edge portions 3t) and 31 on its other side, said offset edges being connected by an abutment edge 32 normal thereto and forming a latching corner or detent 33 with the abutment edge 32. An inwardly projecting latch turning finger 34 is formed on the end edge of the opening 25 facing the latching corner 33 which is located medially between the opposite ends of the opening, said finger 34, the abutment 32 and the corner 33 being adapted to turn the latching element 24 into latching and latch releasing positions with respect to the latching corner 33, in response to successive relative projecting movements of the plates against the influence of the biasing spring, to thereby successively latch the plates in a relatively projected position and to release the same for return to standby position; and it will be seen that the latch actuating and releasing mechanism, including the latching element 24, is of minimal thickness comprising merely the combined thickness of the plates 17 and 19.

One of the plates may be constituted as a support frame and provided with means for securing the same firmly in a base structure in which the device is to be mounted for use, appropriate means being provided for shifting the other plate upon the so constituted support plate, in order to actuate the driven mechanism 11; and while either of the plates may thus be constituted as a support plate, it is convenient, as shown in the illustrated embodiment, to constitute the plate 17, upon which the latching element 24 is carried, as the support plate, by attaching a suitable mounting bracket 35 on an end of the plate.

To this end, the medial portions of the plate 17 may be removed, between the medially mounted latching element 24 and the bracket connected end of the plate, to form a pair of spaced legs 37 for attachment on the bracket and an intervening opening 39, the bracket 35 preferably comprising a bent plate, as of sheet metal, forming a central mounting portion 41 and a pair of spaced parallel wings 43 extending at right angles with respect to the central mounting portion and terminating, remote from said mounting portion, in slotted ends providing spaced clamping fingers 45 for receiving therebetween the terminal ends of the plate mounting finger portions 37. The clamping fingers 45 may be offset inwardly, as at 47, on opposite sides of the bracket 35 and may be soldered, welded, or otherwise secured upon the fingers 37, to thereby rigidly mount the support plate 17 in the bracket 35.

The medial mounting portion 41 of the bracket 35 may be provided with mounting ears 49 formed with openings 51 for the reception of mounting screws, studs or rivets, by means of which the bracket 35, the support plate and the rest of the structure supported thereon may be mounted in operative position, as on a support panel or other mounting base.

The plate 19, at one end, may be formed with an ear 53 haw'ng an opening therethrough, in which opening the headed pin 23 may be secured, as by riveting, in position extending in the elongated slot 21, which may conveniently be formed through the plate 17 on the side of the latching element 24 remote from the bracket connected end of the plate. The headed stud 23 thus not only serves to limit relative movement of the plates in one direction under the influence of the spring 15, by engagement of the stud in the bracket adjacent end 20 of the slot 21, but serves also to limit relative movement of the plates in the opposite direction by engagement of the stud 23 in the opposite end 22 of the slot 21.

The end of the latch actuating plate 19 remote from the ear 53 may be formed with a projecting finger 55 for the actuation of the plate 19. A mounting spool 56 for supporting the preferably helical spring may be secured on the finger 55 adjacent its junction with the plate 19, said spool carrying outstanding flange means 57, at its end remote from the plate 19, for engaging and seating one end of the spring 15. The other end of the spring may seatingly engage a washer 58 having a central opening 59, sized to freely receive the spool for axial sliding movement therethrough, and opposite sides 69 adapted to engage the seats formed in the bracket 35 by the inwardly inclined bracket portions 47, to thus support the spring seating washer 58 on the bracket.

The finger 55 outwardly of the spool 56 is adapted to project through an opening 61 formed centrally in the medial bracket portion 41, and the outer end of the finger 55 may be provided with a suitable pushbutton to facilitate the application of pressure thereon for the purpose of shifting the plate 19 on the support plate 17 in an inward direction away from the bracket. If desired, the opening 61 may be of slot-like configuration to slidingly receive and guide the finger 55; but the opening, as shown, is preferably of circular configuration to slidingly receive the cylindrical portion 52 of a pushbutton element 63 in which cylindrical portion the finger 55 may be embeddedly secured.

The cylindrical portion 62 of the pushbutton element may be formed with longitudinally extending splines 64, and the medial portion 41 of the bracket may be formed with spline grooves 65 in the sides of thev opening 61 to accommodate said splines. Forwardly of the cylindrical portion 62, the pushbutton element 63 may be formed as a hollow housing 66 adapted to contain a mounting socket 67 for a miniature electric lamp 59 of the sort commonly used for pilot light purposes. The pushbutton element may also form a lamp housing chamber 71 having a forwardly end closed by a cover 73 of translucent materials of preferably plastic character, which may have any desired or preferred coloration; and a pair of conductor wires 75 electrically connected with the lamp socket 67 and extending thence longitudinally through the pushbutton element may be provided for electrically energizing the lamp in the chamber 71 to illuminate the translucent cover 73, said conductors having ends 77 extending outwardly of the plate connected end of the pushbutton element for connection with a suitable source of lamp energizing power.

The inner or lamp remote end of the cylindrical portion 62 may be formed integrally with the spring carrying spool 56, and a split bearing washer seated in a groove 78 formed between the cylindrical portion 62 and the spring carrying spool 55 may be provided to form an abutment shoulder providing the spring seating flange means 57.

When the plate 19 is in its normal retracted position, as shown in FIG. 4, the latch element 24 will be held in a starting position extending longitudinally of the support plate 17 by abutment of a side edge of the latch element with the side 31 of the narrow portion 28 of the opening 26 which extends rearwardly of the latching corner 33. When the plate is so positioned in retracted position, one side of the notch 24', in the bracket facing end of the latch element, will be longitudinally alined with the latch shifting finger 34. As a consequence, when the plate 19 is projected on the support plate 17 in a direction away from the bracket 35, against the influence of the spring 15, to the position of maximum projection shown in FIG. 5, as by pressing upon the pushbutton element 63, the abutment wall forming side 31 of the opening 26 will be shifted rearwardly with respect to the latching element 24, thereby presenting it within the wide portion 27 of the opening, and causing the finger 34 to engage in the notch 24 at the bracket facing end of the latch element. The finger 34 and notch 24' are so configurated that upon reaching the bottom of the notch, the finger will have turned the latch element, in the wide portion 27 of the opening 26, about forty-five degrees from its starting position to present the notch at the opposite or bracket remote end of the element 24 in position registering with the latching corner 33. Upon releasing the pushbutton, the compressed spring 15 will cause retrograde movement of the plate 19 from fully projected position to the partially retracted latching position, shown in FIG. 6, in which the latching corner 33 of the plate 19 is engaged in the notch at the corner facing end of the latching element 24.

In order to release the latch and permit the plate 19 to return to its normal retracted position, the plate 19 may be reprojected to its position of maximum projec tion, as by the application of pressure upon the pushbutton element 63, such projecting movement, as shown in FIG.

7, causing the latch actuating finger 34 to engage upon the finger facing side of the element 24 and turn the same from latching position to an intermediate transversely extending position in the wide portion 27 of the opening 26. Release of the pushbutton element 63, when the latching element 24 is in such transversely extending position will cause the abutment 32 and the latching corner 33 to engage with the corner facing side of the latchelement 24 and turn it into its longitudinally extending starting position in abutting relationship with the edge 31 defining the narrow end of the opening 26, as the plate 19 reaches its fully retracted, normal standby position. It will be seen from the foregoing that the finger 34 and abutment 32 serve as latch turning members, and that 7 the opposite sides and notched end surfaces of the latch- 7 switches 81 supported side-by-side on each of the opposite sides of the mounting 79. Although the present invention is not necessarily limited to any particular switch arrangement or array of switches, the switches 81 which are depicted in the illustrated embodiment each comprise a conventional single-pole double-throw switch consisting of a pair of spaced apart spring blades 81-C and 81-1), and an intermediate blade 31-1 forming a pole movable between the spaced blades 81-C and 81-D, in order to make electrical contact with one of said blades or the other, conventional contact making buttons being secured on an end of each of the blades 81-0 and 81-5) and on opposite sides of the pole forming blade til-P. In the illustrated embodiment, the blade 81-? of each switch is normally in electrical contact with the blade 81-C and is not in electrical contact with theblade til-D. The ends of the blades 81-0, 81-1) and 81-1 remote from the contact buttons thereon may be formed as conventional connection lugs or terminals 83, and the blades may be assembled in stacked relation with plates 85 of insulating material and secured together in conventional fashion upon the mounting portion 79 of the support plate 17.

The switches 81 may be mounted on opposite sides of the mounting portion 79 and secured thereto by means of fastening screws 87 extending in alined openings formed in the mounting portion 79, the blades 81-C, 81-D and sl-P, the insulating plates 85 and preferably metallic cover plates 89 overlying the outermost of the insulating plates 85 on opposite sides of the mounting portion 79, the fastening screws 87, of course, being insulated from the blades SI-C, 81-D and 81-1, at the openings therein through which the screws 87 extend; and the assembly may be held together by the threaded engagement of the head remote ends of the screws in one of the cover plates 89, and by the clamping action of the heads of said screws upon the other cover plate. When so mounted on the frame portion 79, the contact carrying ends of the blades Bl-C and Si-D may extend toward the mounting bracket 35, and the pole forming blades 81-? preferably extend toward said bracket substantially beyond the contact carrying ends of the blades til-C and 81-D. The blades 31-? are also preferably formed with cam engaging portions 91 at their bracket adjacent ends.

The latch actuating plate 19 at its junction with the finger 55, adjacent the spring mounting spool 56, may be formed with a pair of laterally opening slots 93 defined between facing shoulders 95, and switch actuating cam means may be anchored on the plate 19 in said slots 93 for movement with the plate 19 longitudinally of the support plate 17, said switch actuating cam means preferably comprising a pair of plates 97 preferably of insulating material, such as fiber board, formed with transversely alined notches 98 and 99 opening on the opposite lateral edges of the cam plates, between the opposite ends thereof, and defining plate mounting portions between the bottoms of the notches 98 and 99, whereby the switch actuating cam plates may be secured on the latch actuating plate 19 in position, with the plate mounting portions 1% extending in the notches 93, and the opposing shoulders 95 interfittingly engaged in the notches 93 and 99, the switch actuating cam plates 97 being secured together in interfitting engagement with the plate 19 by means of fastening pins 101 extending between and secured at their opposite ends to the plates 97.

It will be seen that the opposite ends of the plates 97 extend upon opposite sides of the plate 19 and in the opening 39 of the support plate 17 so that the switch actuating cam plates 97 may move longitudinally of the support plate 17. The opposite ends of the cam plates are formed for engagement with the cam engaging portions 91 of the switch blades it-P. In this connection, the opposite ends of the cam plates 97 have elevated and depressed cam portions MP3 and 105 and inclined portions 107 interconnecting the elevated and depressed portions 103 and 195. The cam plates 97 are secured on the latch actuating plate 19 in position such that the switch actuating portions 91 of the switch blades rest upon the depressed cam portions 195 when the plate 19 is in its retracted or normal standby position shown in PEG. 4. When in such position, the switch blades 81-1 make electrical contact with the switch elements SI-C, as shown in H6. 4a. When the plate 19 is moved from its normal retracted position, into any of the projected positions shown in FIGS. 5, 6 and 7, the switch actuating portions 91 of the blades til-P will ride up the inclined portions 187 and will engage the elevated cam portions H33, in which position the switch blades 832-? will be electrically disconnected from the blades til-C and will be held in electrical contact with the blades ill-D.

Means is also provided in the switch structure for applying electrical energy upon the conductors 75 for operation of the lamp 69. To this end, a pair of leaf spring blades 109 may be secured on the mounting portion 79 of the support plate 17 along with the leaf spring switches 81. The blades 169 may extend side-by-side and on opposite sides of the structure in position immediately above the plate 19 and may have ends 11:) formed for wiping engagement with the ends 77 of the conductors 75 which project outwardly of the lamp remote end of the pushbutton element 63. The projecting ends 77 extend above the plate 19 and are insulated therefrom by means of a plate of insulation 111 clampingly secured by and between the cam plates 97. By forming one of the blades 139 with an offset cam portion 112 and by providing a cam engaging knob 113, preferably of insulating material, upon the plate 19, the lamp 69 may be energized only when the apparatus is in a desired position of adjustment.

As shown, the cam portion 112 and the cam actuating knob 113 are disposed in position f r engagement when the plate 19 is in normal standby or retracted position, thereby separating the blade 1&9 in which the cam 112 is formed from engagement with its associated conductor 77. Accordingly, the lamp 69 will be dark so long as the plate 19 remains in its retracted or standby position shown in FIGS. 1, 4 and 4a. Whenever the plate 19 is in any of its projected positions shown in FIGS. 5, 6 and 7, however, the cam actuating knob 113 will have been shifted into position disengaged from the cam portion 112, as shown in FIGS. 5a and 6a, thereby allowing the end of the blade 169 under the bias of its normal resilience to wipingly engage with its associated conductor 77 whereby to complete the lamp energizing circuit, the blades 109 being provided with connection lugs 115, similar to the lugs 83, for electrical connection with a suitable external source of lamp energizing power. By suitably positioning the cam actuating knob 113, the lamp energizing circuit may be broken when the plate 19 is in either projected or retracted position. By dispensing with the knob entirely, the lamp may be energized continuously regardless of the adjusted position of the plate 19.

It is thought that the invention and its numerous attendant advantages will be fully understood from the foregoing description, and it is obvious that numerous changes may be made in the form, construction and arrangement of the several parts without departing from the spirit or scope of the invention or sacrificing any of its attendant advantages, the form herein disclosed being a preferred embodiment for the purpose of demonstrating the invention.

The invention is hereby claimed as follows:

1. A latching structure comprising a pair of plate-like strips in stacked relationship and secured together for the relative longitudinal movement of one strip on the other, bias means normally urging the movable strip in one direction on the other strip toward a normal retracted position determined by interengaging stop means formed on the strips, means for projecting the movable bias means, a movable latch mounted on one of said.

strips, on the side thereof facing the other strip, and latch engaging mean formed on said other strip, and including a detent and latch shifting members operable to move the latch sucessively into and out of latch engaging position with respect to the detent to thereby successively latch the movable strip in projected position and release the same for return to relatively retracted position in response to successive projection of the movable strip against the influence of the bias means.

2. A latching structure as set forth in claim 1, wherein the movable latch is pivoted for turning movement into and out of detent engaging position on the strip which supports it.

3. A latching structure as set forth in claim 1, wherein the latch comprises a member pivotally mounted for turning movement and formed with a detent engaging notch for latchingly receiving the detent, said member providing cam surfaces for successive latch turning engagement with said latch turning means.

4. A latching structure as set forth in claim 1, wherein the latch comprises an elongated bar medially pivoted for turning movement on the strip which supports it, said bar having oppositely notched ends for latching engagement with the detent and providing cam surfaces for successive latch turning engagement with said latch turning means.

5. A latching structure as set forth in claim 1, wherein the latch engaging means comprises a finger and an abutment shoulder spaced from and facing the finger, whereby said finger and abutment shoulder may successively engage and turn the latch as the movable strip is shifted successively in opposite directions on the other strip.

6. A latching structure as set forth in claim 1, wherein the latch comprises a member turnably mounted on the strip which supports it and providing latch turning cam surfaces for successive engagement with the latch engaging means upon reciprocation of the movable strip, and wherein the latch engaging means comprises an abutment holding the latch normally in released position, when the movable strip is in retracted position on the other strip, a finger positioned to engage a pair of said latch turning cam surfaces to turn the latch successively from released to detent engaging position and from detent engaged to unlatched position in response to successive projection of the movable strip against the bias means, and an abutment shoulder positioned to turn the latch successively from detent engaging to detent engaged position and from unlatched to abutment held released position in response to successive retraction of the movable strip under the influence of the bias means.

7. A latch comprising a pair of sheet metal strips stacked one upon the other and secured together for relative reciprocable movement of one strip on the other between limits determined by cooperating stops on said strips, yielding bias means normally urging the movable strip in one direction toward relatively retracted position on the other strip as determined by a pair of said stops, means operable to project the movable strip in the opposite direction against the influence of said bias means to projected position determined by another pair of said stops, a flat bar forming a latch medially pivoted for turning movement on one of said strips, on the side thereof facing the other strip, said bar having opposite side edges and end edges formed each with a notch having mutually inclined opposite sides, said other strip having spaced apart latch actuating portions formed thereon in position to engage the latch successively in response to reciprocation of the movable strip on the other strip, said portions including a longitudinally extending latch alining abutment in position to extend along a side edge of the latch, when the movable strip is in retracted position, and hold the latch against turning movement in longitudinally oriented unlatched position, and to release the latch upon projection of the movable strip from retractedposition, a latch turning finger positioned to engage a side of an end notch of the latch and to, turn the latch to a latching position as the movable strip is shifted from retracted to projected position, a latching detent in position to engage in an end notch of the latch, when in latching position, and to turn the latch from latching to latched position, in latching engagement with said detent, in response to retrogression of the movable strip from projected position to a partially retracted holding position, said finger being disposed in position to engage a side edge of the latch and turn it from latched to releasing position in response to projection of the movable strip from said partially retracted holding position to projected position, and a latch turning abutment in position to en gage a side edge of the latch and turn it from releasing position to longitudinally oriented unlatched position in response to retraction of the movable strip from projected to retracted position, under the influence of the bias means, when the latch is in said releasing position.

8. An electrical switch structure comprising a pair of plate-like strips in stacked relationship and secured together for the relative longitudinal movement of one strip on the other, bias means normally urging the movable strip in one direction on the other toward a normal retracted position determined by interengaging stop means formed on the strips, means for projecting the movable strip from retracted position against the influence of said bias means, electrical switch means, including a movable sively latch the movable strip in projected position and release the same for return to relatively retracted position in response to successive projection of the movable strip against the influence of the bias means.

9. An electrical switch structure as set forth in claim 8, wherein the movable latch is pivoted for turning movement into and out of detent engaging position on the strip which supports it.

10. An electrical switch structure as set forth in claim 8, wherein the latch comprises a member pivotally mounted for turning movement and formed with a detent engaging notch for latchingly receiving the detent, said member providing cam surfaces for successive latch turning engagement with said latch actuating means.

11. An electrical switch structure as set forth in claim 8, wherein the latch comprises an elongated bar medially pivoted for turning movement on the strip which supports it, said bar having oppositely notched ends for latching engagement with the detent and providing cam surfaces for successive latch turning engagement with said latch actuating means.

12. An electrical switch structure as set forth in claim 8, wherein the latch actuating means comprises a finger and an abutment shoulder spaced from and facing the finger, whereby said finger and abutment shoulder may successively engage and turn the latch as the movable strip is shifted successively in opposite directions on the other strip.

13. An electrical switch structure as set forth in claim 8, wherein the latch comprises a member turnably mounted on the strip which supports it and providing latch turning cam surfaces for successive engagement with the latch engaging means upon reciprocation of the movable strip, and wherein the latch actuating means comprises an abutment holding the latch normally in released position, when the movable strip is in retracted position on the other strip, a finger positioned to engage a pair of said latch turning cam surfaces to turn the latch successively from released to detent engaging position and from detent engaged to unlatched position in responseto successive projection of the movable strip against the bias means, and an abutment shoulder positioned to turn the latch successively from detent engaging to detent engaged position and from unlatched to abutment held released position in response to successive retraction of the movable strip under the influence of the bias means.

14. An electrical switch structure comprising a pair of sheet metal strips stacked one upon the other and secured together for relative reciprocabie movement of one strip on the other between limits determined by coperating stops on said strips, yielding bias means normally urging the movable strip in one direction toward relatively retracted position on the other strip as determined by a pair of said stops, means operable to project the movable strip in the opposite direction against the influence of said bias means to projected position determined by another pair of said stops, electrical switch means, including a movable switch actuating member secured on one of said strips and switch actuating means secured to the other of said strips in position to shift the movable actuating member as the movable strip is projected from and returned to retracted position, a flat bar forming a latch medially pivoted for turning movement on one of said strips, on the side thereof facing the other strip, said bar having opposite side edges and end edges formed each with a notch having mutually inclined opposite sides, said other strip having spaced apart latch actuating portions formed thereon in position to engage the latch successively in response to reciprocation of the movable strip on the other strip, said portions including a longitudinally extending latch alining abutment in position to extend along a side edge of the latch, when the movable strip is in retracted position, and hold the latch against turning movement in longitudinally oriented unlatched position, and to release the latch upon projection of the movable strip from retracted position, a latch turning finger positioned to engage a side of an end notch of the latch and to turn the latch to a latching position as the movable strip is shifted from retracted to projected position, a latching detent in position to engage in an end notch of the latch, when in latching position, and to turn the latch from latching to latched position, in latching engagement with said detent, in response to retrogression of the movable strip from projected position to a partially retracted holding position, said finger being disposed in position to engage a side edge of the latch and turn it from latched to releasing position in response to projection of the movable strip from said partially retracted holding position to projected position, and a latch turning abutment in position to engage a side edge of the latch and turn it from releasing position to longitudinally oriented unlatched position in response to retraction of the movable strip from projected to retracted position, under the influence of the bias means, when the latch is in said releasing position.

15. In a push button controlled structure, a support frame, a shiftable frame reciprocable on the support frame, yielding bias means normally urging the shiftable frame on the support frame in one direction toward a retracted position determined by cooperating stops on said frames, at pushbutton connected with the shiftable frame to move it from retracted position against the influence of said bias means, an electric lamp supporting socket movable with the pushbutton for supporting a lamp in position to illuminate the pushbutton, socket connected conductors on and movable with the shiftable frame, supply conductors on the support frame in position for connection with a source of lamp energizing power, said socket connected and supply conductors being wipingly interconnected, and cooperating cam means on one of said frames and on a said conductor carried on the other frame, said cam means being operable in response to relative movement of said frames to separate a pair of said wipingly interconnected conductors and thereby interrupt the supply of energizing power to said lamp, when the shiftable frame is in a selected position on the support frame.

Davis June 5, 1956 McMains Aug. 15, 1961 

15. IN A PUSH BUTTON CONTROLLED STRUCTURE, A SUPPORT FRAME, A SHIFTABLE FRAME RECIPROCABLE ON THE SUPPORT FRAME, YIELDING BIAS MEANS NORMALLY URGING THE SHIFTABLE FRAME ON THE SUPPORT FRAME IN ONE DIRECTION TOWARD A RETRACTED POSITION DETERMINED BY COOPERATING STOPS ON SAID FRAMES, A PUSHBUTTON CONNECTED WITH THE SHIFTABLE FRAME TO MOVE IT FROM RETRACTED POSITION AGAINST THE INFLUENCE OF SAID BIAS MEANS, AN ELECTRIC LAMP SUPPORTING SOCKET MOVABLE WITH THE PUSHBUTTON FOR SUPPORTING A LAMP IN POSITION TO ILLIMINATE THE PUSHBUTTON, SOCKET CONNECTED CONDUCTORS ON AND MOVABLE WITH THE SHIFTABLE FRAME, SUPPLY CONDUCTORS ON THE SUPPORT FRAME IS POSITION FOR CONNECTION WITH A SOURCE OF LAMP ENERGIZING POWER, SAID SOCKET CONNECTED AND SUPPLY CONDUCTORS BEING WIPINGLY INTERCONNECTED, AND COOPERATING CAM MEANS ON ONE OF SAID FRAMES AND ON A SAID CONDUCTOR CARRIED ON THE OTHER FRAME, SAID CAM MEANS BEING OPERABLE IN RESPONSE TO RELATIVE MOVEMENT OF SAID FRAMES TO SEPARATE A PAIR OF SAID WIPINGLY INTERCONNECTED CONDUCTORS AND THEREBY INTERRUPT THE SUPPLY OF ENERGIZING POWER TO SAID LAMP, WHEN THE SHIFTABLE FRAME IS IN A SELECTED POSITION ON THE SUPPORT FRAME. 